Silicone composition used in the production of antifriction varnishes, method for the application of said varnishes to a support and support thus treated

Abstract

The invention relates to silicone compositions that are used in the production of varnishes that can be applied to supports in order to reduce the friction coefficient. The inventive composition comprises at least one polyorganosiloxane A (POS) which can be cationically and radically cross-linked by functional cross-linking groups (GFR) and a primer C chosen from onium borates, characterized in that the inventive composition also comprises molecules (POS D) which are substituted by secondary functional groups (GFS) carried by silicon atoms and selected from those that include at least one alkoxy and/or epoxy and/or carboxy motif and optionally a charge (e.g. silica). The invention can be used with anti-friction varnishes for RTV silicone coatings for material used in air bags, thermal transfer ribbons or packing films.

1. A silicone composition useful for the production of varnish having anti-friction properties, this composition comprising at least one polyorganosiloxane (POS) which can be crosslinked by means of crosslinking functional groups (CFG) by the cationic and/or free-radical route and an effective quantity of a cationic initiator system comprising, as thermal initiator and/or photoinitiator, a product chosen from the onium salts of an element of groups 15 to 17 of the Periodic Table or the salts of an organometallic complex of an element of groups 4 to 10 of the Periodic Table,
 whose cationic entity is selected from: 
 1) the onium salts of formula (I): 
   [(R 1 ′) n —A—(R 2 ) m ] +   (I)  
 
  in which formula: 
 A represents an element of groups 15 to 17 of the Periodic Table;  
 R 1  represents a carbocyclic or heterocyclic C 6 -C 20  aryl radical, it being possible for said heterocyclic radical to contain, as heteroelements, nitrogen or sulfur;  
 R 2  represents R 1  or a linear or branched C 1 -C 30  alkyl or alkenyl radical, said radicals R 1  and R 2  being optionally substituted with a C 1 -C 25  alkoxy, C 1 -C 25  alkyl, nitro, chloro, bromo, cyano, carboxyl, ester or mercapto group;  
 n is an integer ranging from 1 to v+1, v being the valency of the element A,  
 m is an integer ranging from 0 to v−1 with n+m=v+1;  
 
 2) the oxoisothiochromanium salts;  
 3) the sulfonium salts in which the cationic entity comprises: 
 3-1) at least one polysulfonium species of formula (III-1): 
                 
 
  in which: 
 the symbols Ar 1 , which may be mutually identical or different, each represent a monovalent phenyl or naphthyl radical optionally substituted with one or more radicals chosen from: a linear or branched C 1 -C 12 , alkyl radical, a linear or branched C 1 -C 12 , alkoxy radical, a halogen atom, an —OH group, a —COOH group, an ester group —COO-alkyl where the alkyl portion is a linear or branched C 1 -C 12  residue, and a group of formula —Y 4 —Ar 2  where the symbols Y 4  and Ar 2  have the meanings given just below;  
 the symbols Ar 2 , which may be mutually identical or different, or identical to Ar 1 , each represent a monovalent phenyl or naphthyl radical optionally substituted with one or more radicals chosen from: a linear or branched C 1 -C 12 , alkyl radical, a linear or branched C 1 -C 12 , alkoxy radical, a halogen atom, an —OH group, a —COOH group, an ester group —COO-alkyl where the alkyl portion is a linear or branched C 1 -C 12  residue,  
 the symbols Ar 3 , which may be mutually identical or different, each represent a divalent phenylene or naphthylene radical optionally substituted with one or more radicals chosen from: a linear or branched C 1 -C 12 , alkyl radical, a linear or branched C 1 -C 12 , alkoxy radical, a halogen atom, an —OH group, a —COOH group, an ester group —COO-alkyl where the alkyl portion is a linear or branched C 1 -C 12  residue,  
 t is an integer equal to 0 or 1,  
 
 
 
 
       with the additional conditions according to which:
 a) when t=0, the symbol Y is then a monovalent radical Y 1  representing the group of formula: 
                 
 
  where the symbols Ar 1  and Ar 2  have the meanings given above,  
 b) when t=1:  
 b1) on the one hand, the symbol Y is then a divalent radical having the following meanings Y 2  to Y 4 : 
 Y 2 : a group of formula: 
                 
 
  where the symbol Ar 2  has the meanings given above,  
 Y 3 : a single valency bond,  
 Y 4 : a divalent residue chosen from: 
                 
 
  a linear or branched C 1 -C 12  alkylene residue, and a residue of formula —Si(CH 3 ) 2 O—,  
 
 b2) on the other hand, only in the case where the symbol Y represents Y 3  or Y 4 , the radicals Ar 1  and Ar 2  (terminal) possess, in addition to the meanings given above, the possibility of being linked to each other by the residue Y′ consisting of Y′ 1  a single valency bond or of Y′ 2  a divalent residue chosen from the residues cited in the definition of Y 4 , which is seated between the carbon atoms, facing one another, situated on each aromatic ring at the ortho position with respect to the carbon atom directly linked to the cation S + ; 
 3-2) and/or at least one mono-sulfonium species possessing a single cationic center S +  per mol of cation and consisting of species of formula (III-2): 
                 
 
  in which Ar 1  and Ar 2  have the meanings given above in formula (III-1), including the possibility of directly linking to one another only one of the radicals Ar 1  to Ar 2  in the manner indicated above in the definition of the additional condition which applies when t=1 in formula (III-1), involving the residue Y′;  
 4) the organometallic salts of formula (IV): 
   (L 1 L 2 L 3 M) +q   (IV)  
 
  in which formula: 
 M represents a metal of group 4 to 10 of the Periodic Table;  
 L 1  represents a ligand linked to the metal M by π electrons, a ligand chosen from the ligands η 3 -alkyl, η 5 -cyclopendadienyl and η 7 -cycloheptratrienyl and the η 6 -aromatic compounds chosen from the optionally substituted η 6 -benzene ligands and the compounds having from 2 to 4 fused rings, each ring being capable of contributing to the valency layer of the metal M by 3 to 8 π electrons;  
 L 2  represents a ligand linked to the metal M by π electrons, a ligand chosen from the ligands η 7 -cycloheptatrienyl and the η 6 -aromatic compounds chosen from the optionally substituted η 6 -benzene ligands and the compounds having from 2 to 4 fused rings, each ring being capable of contributing to the valency layer of the metal M by 6 or 7 π electrons;  
 L 3  represents from 0 to 3 identical or different ligands linked to the metal M by π electrons, ligand(s) chosen from CO and NO 2   + ; the total electron charge q of the complex to which L 1 , L 2  and L 3  contribute and the ionic charge of the metal M being positive and equal to 1 or 2;  
 the anionic entity having the formula: 
   [X 1 X 2   a R b ] −   
 
 
 
 
       in which formula:
       a and b are integers ranging, for a, from 0 to 6 and, for b, from 0 to 6 with a+b≧2;    the symbols X 1  represent elements chosen from groups 3A, 4A, 5A of the Periodic Table;    the symbols X 2  represent:     a halogen atom (chlorine, fluorine) with a=0 to 3,     an OH functional group with a=0 to 2;    the symbols R are identical or different and represent: a phenyl radical substituted with at least one electron-attracting group, and/or with at least 2 halogen atoms, and this being when the cationic entity is an onium of an element of groups 15 to 17 of the Periodic Table,        
 a phenyl radical substituted with at least one electron attracting atom or one electron-attracting group, and this being when the cationic entity is an organo-metallic complex of an element of groups 4 to 10 of the Periodic Table,  
 an aryl radical containing at least two aromatic nuclei optionally substituted with at least one electron attracting atom or one electron-attracting group, regardless of the cationic entity;  
 said composition comprising, in addition, molecules substituted with hydrolyzable secondary functional groups (SFG) carried by at least one silicon atom per molecule; with the proviso that either said CFGs and said SFGs are carried by different molecules based on silicon, or said composition comprises POS molecules that are substituted both with CFGs and with SFGs and POS molecules substituted only with CFGs.  
 
     
     
       2. The composition of  claim 1 , wherein said SFGs are selected from the group consisting of alkoxy and/or enoxy and/or carboxyl units. 
     
     
       3. The composition of  claim 1 , wherein it comprises:
 A—at least one POS carrying CFG, the latter being chosen from the groups comprising at least one ethylenically unsaturated functional group;  
 B—at least one silane and/or one POS carrying SFGs, the latter representing at least 1% by weight of B;  
 C—at least one photoinitiator system.  
 
     
     
       4. The composition of  claim 1 , wherein it comprises:
 A—at least one POS carrying CFG, the latter being chosen from the groups comprising at least one ethylenically unsaturated functional group;  
 C—at least one photoinitiator system;  
 D—at least one POS carrying CFGs and SFGS, the CFGs being chosen from groups comprising at least one ethylenically unsaturated functional group.  
 
     
     
       5. The composition of  claim 1 , wherein it comprises in addition:
 E—optionally at least one organic reactive diluent chosen from organic resins of the epoxide and/or vinyl ether and/or oxethane type;  
 F—optionally at least one organic or inorganic pigment;  
 G—optionally a filler;  
 H—optionally at least one photosensitizer.  
 
     
     
       6. The composition of  claim 3 , wherein the POSs A are epoxysilicones and/or vinyl ether silicones which are:
 1) either linear and consist of units of formula (II-1), ending with units of formula (II-2),  
 2) or cyclic and consisting of units of formula (II-1): 
                 
 
  in which formulae: 
 the symbols R 16  are similar or different and represent: 
 either a linear or branched C 1 -C 6  alkyl radical optionally substituted with one or more halogens,  
 or an optionally substituted C 5 -C 8  cycloalkyl radical,  
 or an aryl or aralkyl radical optionally substituted with halogens and/or alkoxyls,  
 
 the symbols Z are similar or different and represent: either the radical R 16 , 
 or a CFG group corresponding to an epoxide or vinyl ether residue linked to the silicon by means of a divalent radical containing from 2 to 20 carbon atoms optionally comprising a heteroatom, at least one of the symbols Z corresponding to a CFG group.  
 
 
 
     
     
       7. The composition of  claim 3 , wherein the POSs A are epoxysilicones and/or vinyl ether silicones which are:
 1) either linear and consist of units of formula (II-1), ending with units of formula(II-2),  
 2) or cyclic and consisting of units of formula (II-1): 
                 
 
  in which formulae: 
 the symbols R 16  are similar or different and represent: 
 either a linear or branched C 1 -C 6  alkyl radical substituted with one or more halogens, the substituted alkyl radicals being: methyl, ethyl, propyl, octyl and 3,3,3-trifluoropropyl,  
 or an optionally substituted C 5 -C 8  cycloalkyl radical,  
 or an aryl or aralkyl radical optionally substituted with halogens and/or alkoxyls,  
 and at least 60 mol % of the R 16  radicals being methyls,  
 
 the symbols Z are similar or different and represent: either the radical R 16 , 
 or a CFG group corresponding to an epoxide or vinyl ether residue linked to the silicon by means of a divalent radical containing from 2 to 20 carbon atoms optionally comprising a heteroatom, at least one of the symbols Z corresponding to a CFG group.  
 
 
 
     
     
       8. The composition of  claim 3 , wherein the POSs A are epoxysilicones of the following formulae (A-I) (A-II): 
                 
 
       with X=CH 3 ; phenyl; cycloalkyl; C 1 -C 18  alkyl; alkenyl; —OH; H; CH 2  —CH 2 —CH 2 —OH; CH 2 —CH 2 —CF 3 ; or —(CH 2 ) n —CF 3 , n=1 to 20; 
                 
 
       a 1 , a 2  and b 1 , b 2  being defined as below in formulae (A-I) and (A-II)
   1≦a 1 , a 2  1≦b 1 , b 2 ;  
 
       a 2 , b 2  being=0 in formula (A-II) to give the epoxidized disiloxane (A-III). 
     
     
       9. The composition of  claim 3 , wherein the compound(s) B is (are) chosen from that (or those) of the following formula B:
   R 22   x [SFG] y SiO 4−(x+y)/2   (B)  
 
       in which:
 x=0, 1, 2 or 3  
 y=1, 2, 3 or 4  
 x+y≦4  
 the radicals R 22  are mutually identical or different and correspond to a linear or branched alkyl, a cycloalkyl, a hydroxyl, a hydrogen, a vinyl, a —CF 3 , or a —(CH 2 ) m —CF 3  with m=1 to 50,  
 the SFGs are mutually identical or different and correspond to an alkoxy; an enoxy; or a carboxyl.  
 
     
     
       10. The composition of  claim 3 , wherein the compound(s) B is (are) chosen from that (or those) of the following formula B:
   R 22   x [SFG] y SiO 4−(x+y)/2   (B)  
 
       in which:
 x=0, 1, 2 or 3  
 y=1, 2, 3 or 4  
 x+y≦4  
 the radicals R 22  are mutually identical or different and correspond to a linear or branched alkyl, a cycloalkyl, a hydroxyl, a hydrogen, a vinyl, a —CF 3 , or a —(CH 2 ) m —CF 3  with m=1 to 50,  
 the SFGs are mutually identical or different and correspond to: 
 —OR 3  with R 3  representing a linear or branched C 1 -C 30  alkyl or a cycloalkyl;  
 
 —(OR 4 ) p —OR 5 ; 
 —(R 6 ) q —Si(OR 7 ) r (R 8 ) t    
 
 with R 4 , R 7 , R 8  mutually identical or different and having the same definition as that given above for R 3  and with R 6  mutually identical or different and corresponding to an alkylene; p, q=1 to 50; r=1, 2 or 3 and t=0, 1 or 2; r+t=3; 
 —O—CH═CH—R 8 ;  
 —(R 9 ) u —Si(OCH═CHR 10 ) v (R 11 ) w    
 
 with R 8 , R 10 , R 11  mutually identical or different and having the same definition as that given above for R 3 , and with R 9  having the same definition as that given above for R 6 ; u=1 to 50, v=1, 2 or 3 and w=0, 1 or 2; v+w=3; 
 —OCOR 12 ;  
 (R 13 ) z —Si(OCOR 14 ) z1 (R 15 ) z2 ;  
 
 with R 12 , R 14  as defined above for R 8 , R 10 , R 11 ; R 13  as defined above for R 9 ; and z=1 to 50, z 1 =1, 2 or 3 and z 2 =0, 1 or 2; z 1 +z 2 =3.  
 
     
     
       11. The composition of  claim 4 , wherein the POS D comprises
 SFGs corresponding to an alkoxy; an enoxy; or a carboxyl;  
 and CFGs of the (meth)acrylate and/or vinyl ether and/or epoxide and/or oxethane type.  
 
     
     
       12. The composition of  claim 4 , wherein the POS D comprises SFGs of the alkoxy type and CFGs of the epoxide type. 
     
     
       13. The composition of  claim 4 , wherein the POS D corresponds to the POSs of the following formulae (D′, D″, D′″): 
                 
 
       with Me=methyl; Et=ethyl and 0≦e. 
     
     
       14. The silicone composition of  claim 1 , wherein:
 said cationic entity is selected from: 
 1) the onium salts of formula (I): 
   [(R 1 ) n —A—(R 2 ) m ] +   (I)  
 
  in which formula: 
 A represents an element of groups 15 to 17 of the Periodic Table, selected from the group consisting of I, S, Se, P or N; and R 1 , R 2 , n and m have the same meaning as above;  
 
 2) the oxoisothiochromanium salts selected from the group consisting of the sulfonium salt of 2-ethyl-4-oxoisothiochromanium or of 2-dodecyl-4-oxoisothiochromanium;  
 3) said sulfonium salts;  
 4) the organometallic salts of formula (IV): 
   (L 1 L 2 L 3 M) +q   (IV)  
 
  in which formula: 
 M represents a metal of group 4 to 10 of the Periodic Table, selected from the group consisting of iron, manganese, chromium, cobalt; L 1 , L 2  and L 3 have the same meaning as above;  
 the anionic entity having the formula: [X 1 X 2   a R b ] −  in which formula:  
 a, b and X 1  have the same meaning as above;  
 the symbols X 2  represent: 
 a chlorine atom or a fluorine atom, with a=0 to 3,  
 an OH functional group with a=0 to 2;  
 
 the symbols R are identical or different and represent:a phenyl radical substituted with at least one electron-attracting group selected from the group consisting of OCF 3 , CF 3 , NO 2 , CN, and/or with at least 2 fluorine atoms, and this being when the cationic entity is an onium of an element of groups 15 to 17 of the Periodic Table,  
 
 
 a phenyl radical substituted with at least one electron attracting atom or one electron-attracting group, selected from the group consisting of a fluorine atom, CF 3 , OCF 3 , NO 2 , CN, and this being when the cationic entity is an organo-metallic complex of an element of groups 4 to 10 of the Periodic Table,  
 an aryl radical containing at least two aromatic nuclei selected from the group consisting of biphenyl, naphthyl, optionally substituted with at least one electron attracting atom or one electron attracting group, selected from the group consisting of a fluorine atom, OCF 3 , CF 3 , NO 2 , CN, regardless of the cationic entity.  
 
     
     
       15. A method of applying an antifriction varnish layer to a support, comprising
 coating a support with a silicone composition, and  
 exposing the surface thus coated to actinic radiation and/or to a beam of electrons and/or to heat, so as to cause the crosslinking of the silicone composition and obtain an antifriction varnish layer,  
 wherein said silicone composition comprises at least one polyorganosiloxane (POS) which can be crosslinked by means of crosslinking functional groups (CFG) by the cationic and/or free-radical route and an effective quantity of a cationic initiator system comprising, as thermal initiator and/or photoinitiator, a product chosen from the onium salts of an element of groups 15 to 17 of the Periodic Table or the salts of an organometallic complex of an element of groups 4 to 10 of the Periodic Table,  
 whose cationic entity is selected from: 
 1) the onium salts of formula (I): 
   [(R 1 ) n —A—(R 2 ) m ] +   (I)  
 
  in which formula: 
 A represents an element of groups 15 to 17 of the Periodic Table;  
 R 1  represents a carbocyclic or heterocyclic C 6 -C 20  aryl radical, it being possible for said heterocyclic radical to contain, as heteroelements, nitrogen or sulfur;  
 R 2  represents R 1  or a linear or branched C 1 -C 30  alkyl or alkenyl radical, said radicals R 1  and R 2  being optionally substituted with a C 1 -C 25  alkoxy, C 1 -C 25  alkyl, nitro, chloro, bromo, cyano, carboxyl, ester or mercapto group;  
 n is an integer ranging from 1 to v+1, v being the valency of the element A,  
 m is an integer ranging from 0 to v−1 with n+m=v+1;  
 
 2) the oxoisothiochromanium salts;  
 3) the sulfonium salts in which the cationic entity comprises: 
 3-1) at least one polysulfonium species of formula (III-1): 
                 
 
  in which: 
 the symbols Ar 1 , which may be mutually identical or different, each represent a monovalent phenyl or naphthyl radical optionally substituted with one or more radicals chosen from: a linear or branched C 1 -C 12 , alkyl radical, a linear or branched C 1 -C 12 , alkoxy radical, a halogen atom, an —OH group, a —COOH group, an ester group —COO-alkyl where the alkyl portion is a linear or branched C 1 -C 12  residue, and a group of formula —Y 4 —Ar 2  where the symbols Y 4  and Ar 2  have the meanings given just below;  
 the symbols Ar 2 , which may be mutually identical or different, or identical to Ar 1 , each represent a monovalent phenyl or naphthyl radical optionally substituted with one or more radicals chosen from: a linear or branched C 1 -C 12 , alkyl radical, a linear or branched C 1 -C 12 , alkoxy radical, a halogen atom, an —OH group, a —COOH group, an ester group —COO-alkyl where the alkyl portion is a linear or branched C 1 -C 12  residue,  
 the symbols Ar 3 , which may be mutually identical or different, each represent a divalent phenylene or naphthylene radical optionally substituted with one or more radicals chosen from: a linear or branched C 1 -C 12 , alkyl radical, a linear or branched C 1 -C 12 , alkoxy radical, a halogen atom, an —OH group, a —COOH group, an ester group —COO-alkyl where the alkyl portion is a linear or branched C 1 -C 12  residue,  
 t is an integer equal to 0 or 1,  
 
 
 
 
       with the additional conditions according to which:
 a) when t=0, the symbol Y is then a monovalent radical Y 1  representing the group of formula: 
                 
 
  where the symbols Ar 1  and Ar 2  have the meanings given above,  
 b) when t=1: 
 b1) on the one hand, the symbol Y is then a divalent radical having the following meanings Y 2  to Y 4 : 
 Y 2 : a group of formula: 
                 
 
  where the symbol Ar 2  has the meanings given above,  
 Y 3 : a single valency bond,  
 Y 4 : a divalent residue chosen from: 
                 
 
  a linear or branched C 1 -C 12  alkylene residue, and a residue of formula —Si(CH 3 ) 2 O—,  
 
 b2) on the other hand, only in the case where the symbol Y represents Y 3  or Y 4 , the radicals Ar 1  and Ar 2  (terminal) possess, in addition to the meanings given above, the possibility of being linked to each other by the residue Y′ consisting of Y′ 1  a single valency bond or of Y′ 2  a divalent residue chosen from the residues cited in the definition of Y 4 , which is seated between the carbon atoms, facing one another, situated on each aromatic ring at the ortho position with respect to the carbon atom directly linked to the cation S + ; 
 3-2) and/or at least one mono-sulfonium species, possessing a single cationic center S +  per mol of cation and consisting of species of formula (III-2): 
                 
 
  in which Ar 1  and Ar 2  have the meanings given above in formula (III-1), including the possibility of directly linking to one another only one of the radicals Ar 1  to Ar 2  in the manner indicated above in the definition of the additional condition which applies when t=1 in formula (III-1), involving the residue Y′;  
 
 4) the organometallic salts of formula (IV):  
 
 
        (L 1 L 2 L 3 M) +q   (IV)
    in which formula: 
 M represents a metal of group 4 to 10 of the Periodic Table;  
 L 1  represents a ligand linked to the metal M by π electrons, a ligand chosen from the ligands η 3 -alkyl, η 5 -cyclopendadienyl and η 7 -cycloheptratrienyl and the η 6 -aromatic compounds chosen from the optionally substituted η 6 -benzene ligands and the compounds having from 2 to 4 fused rings, each ring being capable of contributing to the valency layer of the metal M by 3 to 8 π electrons;  
 L 2  represents a ligand linked to the metal M by π electrons, a ligand chosen from the ligands η 7 -cycloheptatrienyl and the η 6 -aromatic compounds chosen from the optionally substituted η 6 -benzene ligands and the compounds having from 2 to 4 fused rings, each ring being capable of contributing to the valency layer of the metal M by 6 or 7 π electrons;  
 L 3  represents from 0 to 3 identical or different ligands linked to the metal M by π electrons, ligand(s) chosen from CO and NO 2   + ; the total electron charge q of the complex to which L 1 , L 2  and L 3  contribute and the ionic charge of the metal M being positive and equal to 1 or 2;  
 the anionic entity having the formula: 
   [X 1 X 2   a R b ] −   
 
   
 
       in which formula:
       a and b are integers ranging, for a, from 0 to 6 and, for b, from 0 to 6 with a+b≧2;    the symbols X 1  represent elements chosen from groups 3A, 4A, 5A of the Periodic Table;    the symbols X 2  represent:     a halogen atom (chlorine, fluorine) with a=0 to 3,     an OH functional group with a=0 to 2;    the symbols R are identical or different and represent: a phenyl radical substituted with at least one electron attracting group, and/or with at least 2 halogen atoms, and this being when the cationic entity is an onium of an element of groups 15 to 17 of the Periodic Table,        
 a phenyl radical substituted with at least one electron attracting atom or one electron attracting group, and this being when the cationic entity is an organo-metallic complex of an element of groups 4 to 10 of the Periodic Table,  
 an aryl radical containing at least two aromatic nuclei optionally substituted with at least one electron attracting atom or one electron-attracting group, regardless of the cationic entity;  
 said composition comprising, in addition, molecules substituted with hydrolyzable secondary functional groups (SFG) carried by at least one silicon atom per molecule; with the proviso that either said CFGs and said SFGs are carried by different molecules based on silicon, or said composition comprises POS molecules that are substituted both with CFGs and with SFGs and POS molecules substituted only with CFGs.  
 
     
     
       16. A varnish support having antifriction properties, said support comprising a substrate coated on at least one of its surfaces with at least one layer of silicone elastomer which can be crosslinked or which is at least partially crosslinked,
 said antifriction varnish obtained from a silicone composition comprising at least one polyorganosiloxane (POS) which can be crosslinked by means of crosslinking functional groups (CFG) by the cationic and/or free-radical route and an effective quantity of a cationic initiator system comprising, as thermal initiator and/or photoinitiator, a product chosen from the onium salts of an element of groups 15 to 17 of the Periodic Table or the salts of an organometallic complex of an element of groups 4 to 10 of the Periodic Table,  
 whose cationic entity is selected from: 
 1) the onium salts of formula (I): 
   [(R 1 ) n —A—(R 2 ) m ] +   (I)  
 
  in which formula: 
 A represents an element of groups 15 to 17 of the Periodic Table;  
 R 1  represents a carbocyclic or heterocyclic C 6 -C 20  aryl radical, it being possible for said heterocyclic radical to contain, as heteroelements, nitrogen or sulfur;  
 R 2  represents R 1  or a linear or branched C 1 -C 30  alkyl or alkenyl radical, said radicals R 1  and R 2  being optionally substituted with a C 1 -C 25  alkoxy, C 1 -C 25  alkyl, nitro, chloro, bromo, cyano, carboxyl, ester or mercapto group;  
 n is an integer ranging from 1 to v+1, v being the valency of the element A,  
 m is an integer ranging from 0 to v−1 with n+m=v+1;  
 
 2) the oxoisothiochromanium salts;  
 3) the sulfonium salts in which the cationic entity comprises: 
 3-1) at least one polysulfonium species of formula (III-1): 
                 
 
  in which: 
 the symbols Ar 1 , which may be mutually identical or different, each represent a monovalent phenyl or naphthyl radical optionally substituted with one or more radicals chosen from: a linear or branched C 1 -C 12 , alkyl radical, a linear or branched C 1 -C 12 , alkoxy radical, a halogen atom, an —OH group, a —COOH group, an ester group —COO-alkyl where the alkyl portion is a linear or branched C 1 -C 12  residue, and a group of formula —Y 4 —Ar 2  where the symbols Y 4  and Ar 2  have the meanings given just below;  
 the symbols Ar 2 , which may be mutually identical or different, or identical to Ar 1 , each represent a monovalent phenyl or naphthyl radical optionally substituted with one or more radicals chosen from: a linear or branched C 1 -C 12 , alkyl radical, a linear or branched C 1 -C 12 , alkoxy radical, a halogen atom, an —OH group, a —COOH group, an ester group —COO-alkyl where the alkyl portion is a linear or branched C 1 -C 12  residue,  
 the symbols Ar 3 , which may be mutually identical or different, each represent a divalent phenylene or naphthylene radical optionally substituted with one or more radicals chosen from: a linear or branched C 1 -C 12 , alkyl radical, a linear or branched C 1 -C 12 , alkoxy radical, a halogen atom, an —OH group, a —COOH group, an ester group —COO-alkyl where the alkyl portion is a linear or branched C 1 -C 12  residue,  
 t is an integer equal to 0 or 1,  
 
 
 
 
       with the additional conditions according to which:
 a) when t=0, the symbol Y is then a monovalent radical Y 1  representing the group of formula: 
                 
 
  where the symbols Ar 1  and Ar 2  have the meanings given above,  
 b) when t=1: 
 b1) on the one hand, the symbol Y is then a divalent radical having the following meanings Y 2  to Y 4 : 
 Y 2 : a group of formula: 
                 
 
  where the symbol Ar 2  has the meanings given above,  
 Y 3 : a single valency bond,  
 Y 4 : a divalent residue chosen from: 
                 
 
  a linear or branched C 1 -C 12  alkylene residue, and a residue of formula —Si(CH 3 ) 2 O—,  
 
 b2) on the other hand, only in the case where the symbol Y represents Y 3  or Y 4 , the radicals Ar 1  and Ar 2  (terminal) possess, in addition to the meanings given above, the possibility of being linked to each other by the residue Y′ consisting of Y′ 1  a single valency bond or of Y′ 2  a divalent residue chosen from the residues cited in the definition of Y 4 , which is seated between the carbon atoms, facing one another, situated on each aromatic ring at the ortho position with respect to the carbon atom directly linked to the cation S + ; 
 3-2) and/or at least one mono-sulfonium species possessing a single cationic center S +  per mol of cation and consisting of species of formula (III-2): 
                 
 
  in which Ar 1  and Ar 2  have the meanings given above in formula (III-1), including the possibility of directly linking to one another only one of the radicals Ar 1  to Ar 2  in the manner indicated above in the definition of the additional condition which applies when t=1 in formula (III-1), involving the residue Y′;  
 
 4) the organometallic salts of formula (IV): 
   (L 1 L 2 L 3 M) +q   (IV)  
 
  in which formula: 
 M represents a metal of group 4 to 10 of the Periodic Table;  
 L 1  represents a ligand linked to the metal M by π electrons, a ligand chosen from the ligands η 3 -alkyl, η 5 -cyclopendadienyl and η 7 -cycloheptratrienyl and the η 6 -aromatic compounds chosen from the optionally substituted η 6 -benzene ligands and the compounds having from 2 to 4 fused rings, each ring being capable of contributing to the valency layer of the metal M by 3 to 8 π electrons;  
 L 2  represents a ligand linked to the metal M by π electrons, a ligand chosen from the ligands η 7 -cycloheptatrienyl and the η 6 -aromatic compounds chosen from the optionally substituted η 6 -benzene ligands and the compounds having from 2 to 4 fused rings, each ring being capable of contributing to the valency layer of the metal M by 6 or 7 π electrons;  
 L 3  represents from 0 to 3 identical or different ligands linked to the metal M by π electrons, ligand(s) chosen from CO and NO 2   + ; the total electron charge q of the complex to which L 1 , L 2  and L 3  contribute and the ionic charge of the metal M being positive and equal to 1 or 2;  
 the anionic entity having the formula: 
   [X 1 X 2   a R b ] −   
 
 
 
 
       in which formula:
       a and b are integers ranging, for a, from 0 to 6 and, for b, from 0 to 6 with a+b≧2;    the symbols X 1  represent elements chosen from groups 3A, 4A, 5A of the Periodic Table;    the symbols X 2  represent:     a halogen atom (chlorine, fluorine) with a=0 to 3,     an OH functional group with a=0 to 2;    the symbols R are identical or different and represent: a phenyl radical substituted with at least one electron-attracting group, and/or with at least 2 halogen atoms, and this being when the cationic entity is an onium of an element of groups 15 to 17 of the Periodic Table,        
 a phenyl radical substituted with at least one electron attracting atom or one electron-attracting group, and this being when the cationic entity is an organo-metallic complex of an element of groups 4 to 10 of the Periodic Table,  
 an aryl radical containing at least two aromatic nuclei optionally substituted with at least one electron attracting atom or one electron-attracting group, regardless of the cationic entity;  
 said composition comprising, in addition, molecules substituted with hydrolyzable secondary functional groups (SFG) carried by at least one silicon atom per molecule; with the proviso that either said CFGs and said SFGs are carried by different molecules based on silicon, or said composition comprises POS molecules that are substituted both with CFGs and with SFGs and POS molecules substituted only with CFGs;  
 said antifriction varnish being applied to the (top) layer(s) of silicone elastomer.  
 
     
     
       17. The varnish support of  claim 16 , wherein said at least one layer of silicone elastomer can be crosslinked or is at least partially crosslinked, and chosen from the polyaddition or polycondensation RTV silicones, and/or the peroxide HVE silicones, and/or the polyaddition LSR silicones. 
     
     
       18. The varnish support of  claim 16 , wherein it is intended to be used for the manufacture of inflatable bags for the personal protection of the occupants of vehicles, thermal transfer ribbons or protective wrapping films. 
     
     
       19. An inflatable bag for the personal protection of the occupants of vehicles, produced from the support of  claim 16 . 
     
     
       20. A thermal transfer ribbon, produced from the support of  claim 16 . 
     
     
       21. A wrapping film, produced from the support of  claim 16 . 
     
     
       22. A silicone composition useful for the production of varnish having anti-friction properties, comprising
 at least one polyorganosiloxane (POS) which can be crosslinked by means of crosslinking functional groups (CFG) by the cationic and/or free-radical route,  
 molecules substituted with hydrolyzable secondary functional groups (SFG) carried by at least one silicon atom per molecule; with the proviso that either said CFGs and said SFGs are carried by different molecules based on silicon, or said composition comprises POS molecules that are substituted both with CFGs and with SFGs and POS molecules substituted only with CFGs, and  
 an effective quantity of a cationic initiator system comprising, as thermal initiator and/or photoinitiator, a product chosen from the onium salts of an element of groups 15 to 17 of the Periodic Table or the salts of an organometallic complex of an element of groups 4 to 10 of the Periodic Table.